Hello All,
I am using the energy plus software for simulating a building model at
Barcelona,Spain. For this, I am facing the problem of repetitive warning-
** Warning ** CalcDoe2DXCoil: Coil:Cooling:DX:SingleSpeed "C4 AHU COOLING
COIL" - Full load outlet air dry-bulb temperature < 2C.
This indicates the possibility of coil frost/freeze. Outlet temperature =
1.13 C.
** ~~~ ** ...Occurrence info = BAR? VIVER, 01/04 17:07 - 17:10
** ~~~ ** ... Possible reasons for low outlet air dry-bulb
temperatures are: This DX coil
** ~~~ ** 1) may have a low inlet air dry-bulb temperature. Inlet
air temperature = 18.533 C.
** ~~~ ** 2) may have a low air flow rate per watt of cooling
capacity. Check inputs.
** ~~~ ** 3) is used as part of a HX assisted cooling coil which
uses a high sensible effectiveness. Check inputs.
************* ** Warning ** CalcDoe2DXCoil:
Coil:Cooling:DX:SingleSpeed="C4 AHU COOLING COIL" - Full load outlet
temperature indicates a possibility of frost/freeze error continues. Outlet
air temperature statistics follow:
************* ** ~~~ ** during Warmup 0 times;
************* ** ~~~ ** during Sizing 0 times.
************* ** ~~~ ** Max=1.996617 Min=-1.058986
The above mentioned problem is occurring many time and I have checked all
the parameters related to Cooling Coil but it is not solved.
Please suggest our comments...
--
With Regards
Sheelam Khare
Dear Sheelam,
There is a helpful online document by the LBNL simulations group that says the following:
Quoting:
"This particular warning tells you that the DX cooling equipment should not be operated at very cold outdoor dry-bulb temperatures. Although you cannot damage a DX compressor in a simulation, you can damage it in real life andthis warning is meant to help you select the appropriate type of equipment for your application. Cooling is not typically required when outdoor temperatures are very cold. If cooling is required when outdoor temperatures are very low, maybe a hydronic system would be better."
Source:http://simulationresearch.lbl.gov/dirun/28sep.pdf
Regards,
Alex